Field effectiveness of pandemic and 2009-2010 seasonal vaccines against 2009-2010 A(H1N1) influenza: estimations from surveillance data in France. 2011

Camille Pelat, and Alessandra Falchi, and Fabrice Carrat, and Anne Mosnier, and Isabelle Bonmarin, and Clément Turbelin, and Sophie Vaux, and Sylvie van der Werf, and Jean Marie Cohen, and Bruno Lina, and Thierry Blanchon, and Thomas Hanslik
UPMC Université Paris 06, UMRS 707, Paris, France. pelat@u707.jussieu.fr

BACKGROUND In this study, we assess how effective pandemic and trivalent 2009-2010 seasonal vaccines were in preventing influenza-like illness (ILI) during the 2009 A(H1N1) pandemic in France. We also compare vaccine effectiveness against ILI versus laboratory-confirmed pandemic A(H1N1) influenza, and assess the possible bias caused by using non-specific endpoints and observational data. RESULTS We estimated vaccine effectiveness by using the following formula: VE  =  (PPV-PCV)/(PPV(1-PCV)) × 100%, where PPV is the proportion vaccinated in the population and PCV the proportion of vaccinated influenza cases. People were considered vaccinated three weeks after receiving a dose of vaccine. ILI and pandemic A(H1N1) laboratory-confirmed cases were obtained from two surveillance networks of general practitioners. During the epidemic, 99.7% of influenza isolates were pandemic A(H1N1). Pandemic and seasonal vaccine uptakes in the population were obtained from the National Health Insurance database and by telephonic surveys, respectively. Effectiveness estimates were adjusted by age and week. The presence of residual biases was explored by calculating vaccine effectiveness after the influenza period. The effectiveness of pandemic vaccines in preventing ILI was 52% (95% confidence interval: 30-69) during the pandemic and 33% (4-55) after. It was 86% (56-98) against confirmed influenza. The effectiveness of seasonal vaccines against ILI was 61% (56-66) during the pandemic and 19% (-10-41) after. It was 60% (41-74) against confirmed influenza. CONCLUSIONS The effectiveness of pandemic vaccines in preventing confirmed pandemic A(H1N1) influenza on the field was high, consistently with published findings. It was significantly lower against ILI. This is unsurprising since not all ILI cases are caused by influenza. Trivalent 2009-2010 seasonal vaccines had a statistically significant effectiveness in preventing ILI and confirmed pandemic influenza, but were not better in preventing confirmed pandemic influenza than in preventing ILI. This lack of difference might be indicative of selection bias.

UI MeSH Term Description Entries
D007223 Infant A child between 1 and 23 months of age. Infants
D007251 Influenza, Human An acute viral infection in humans involving the respiratory tract. It is marked by inflammation of the NASAL MUCOSA; the PHARYNX; and conjunctiva, and by headache and severe, often generalized, myalgia. Grippe,Human Flu,Human Influenza,Influenza in Humans,Influenza,Flu, Human,Human Influenzas,Influenza in Human,Influenzas,Influenzas, Human
D007252 Influenza Vaccines Vaccines used to prevent infection by viruses in the family ORTHOMYXOVIRIDAE. It includes both killed and attenuated vaccines. The composition of the vaccines is changed each year in response to antigenic shifts and changes in prevalence of influenza virus strains. The flu vaccines may be mono- or multi-valent, which contains one or more ALPHAINFLUENZAVIRUS and BETAINFLUENZAVIRUS strains. Flu Vaccine,Influenzavirus Vaccine,Monovalent Influenza Vaccine,Universal Flu Vaccine,Universal Influenza Vaccine,Flu Vaccines,High-Dose Trivalent Influenza Vaccine,Influenza Vaccine,Influenza Virus Vaccine,Influenza Virus Vaccines,Influenzavirus Vaccines,Intranasal Live-Attenuated Influenza Vaccine,LAIV Vaccine,Monovalent Influenza Vaccines,Quadrivalent Influenza Vaccine,Trivalent Influenza Vaccine,Trivalent Live Attenuated Influenza Vaccine,Universal Flu Vaccines,Universal Influenza Vaccines,Flu Vaccine, Universal,High Dose Trivalent Influenza Vaccine,Influenza Vaccine, Monovalent,Influenza Vaccine, Quadrivalent,Influenza Vaccine, Trivalent,Influenza Vaccine, Universal,Intranasal Live Attenuated Influenza Vaccine,Vaccine, Flu,Vaccine, Influenza,Vaccine, Influenza Virus,Vaccine, Influenzavirus,Vaccine, LAIV,Vaccine, Monovalent Influenza,Vaccine, Quadrivalent Influenza,Vaccine, Trivalent Influenza,Virus Vaccine, Influenza
D008875 Middle Aged An adult aged 45 - 64 years. Middle Age
D011159 Population Surveillance Ongoing scrutiny of a population (general population, study population, target population, etc.), generally using methods distinguished by their practicability, uniformity, and frequently their rapidity, rather than by complete accuracy. Surveillance, Population
D002648 Child A person 6 to 12 years of age. An individual 2 to 5 years old is CHILD, PRESCHOOL. Children
D002675 Child, Preschool A child between the ages of 2 and 5. Children, Preschool,Preschool Child,Preschool Children
D005602 France A country in western Europe bordered by the Atlantic Ocean, the English Channel, the Mediterranean Sea, and the countries of Belgium, Germany, Italy, Spain, Switzerland, the principalities of Andorra and Monaco, and by the duchy of Luxembourg. Its capital is Paris. Corsica,Saint Pierre and Miquelon,Miquelon and Saint Pierre,Miquelon and St. Pierre,St. Pierre and Miquelon
D006801 Humans Members of the species Homo sapiens. Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000293 Adolescent A person 13 to 18 years of age. Adolescence,Youth,Adolescents,Adolescents, Female,Adolescents, Male,Teenagers,Teens,Adolescent, Female,Adolescent, Male,Female Adolescent,Female Adolescents,Male Adolescent,Male Adolescents,Teen,Teenager,Youths

Related Publications

Camille Pelat, and Alessandra Falchi, and Fabrice Carrat, and Anne Mosnier, and Isabelle Bonmarin, and Clément Turbelin, and Sophie Vaux, and Sylvie van der Werf, and Jean Marie Cohen, and Bruno Lina, and Thierry Blanchon, and Thomas Hanslik
July 2011, Emerging infectious diseases,
Camille Pelat, and Alessandra Falchi, and Fabrice Carrat, and Anne Mosnier, and Isabelle Bonmarin, and Clément Turbelin, and Sophie Vaux, and Sylvie van der Werf, and Jean Marie Cohen, and Bruno Lina, and Thierry Blanchon, and Thomas Hanslik
January 2011, Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin,
Camille Pelat, and Alessandra Falchi, and Fabrice Carrat, and Anne Mosnier, and Isabelle Bonmarin, and Clément Turbelin, and Sophie Vaux, and Sylvie van der Werf, and Jean Marie Cohen, and Bruno Lina, and Thierry Blanchon, and Thomas Hanslik
March 2013, Epidemiology and infection,
Camille Pelat, and Alessandra Falchi, and Fabrice Carrat, and Anne Mosnier, and Isabelle Bonmarin, and Clément Turbelin, and Sophie Vaux, and Sylvie van der Werf, and Jean Marie Cohen, and Bruno Lina, and Thierry Blanchon, and Thomas Hanslik
July 2012, Vaccine,
Camille Pelat, and Alessandra Falchi, and Fabrice Carrat, and Anne Mosnier, and Isabelle Bonmarin, and Clément Turbelin, and Sophie Vaux, and Sylvie van der Werf, and Jean Marie Cohen, and Bruno Lina, and Thierry Blanchon, and Thomas Hanslik
February 2011, Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin,
Camille Pelat, and Alessandra Falchi, and Fabrice Carrat, and Anne Mosnier, and Isabelle Bonmarin, and Clément Turbelin, and Sophie Vaux, and Sylvie van der Werf, and Jean Marie Cohen, and Bruno Lina, and Thierry Blanchon, and Thomas Hanslik
January 2010, Emerging infectious diseases,
Camille Pelat, and Alessandra Falchi, and Fabrice Carrat, and Anne Mosnier, and Isabelle Bonmarin, and Clément Turbelin, and Sophie Vaux, and Sylvie van der Werf, and Jean Marie Cohen, and Bruno Lina, and Thierry Blanchon, and Thomas Hanslik
September 2011, Vaccine,
Camille Pelat, and Alessandra Falchi, and Fabrice Carrat, and Anne Mosnier, and Isabelle Bonmarin, and Clément Turbelin, and Sophie Vaux, and Sylvie van der Werf, and Jean Marie Cohen, and Bruno Lina, and Thierry Blanchon, and Thomas Hanslik
March 2010, The Journal of allergy and clinical immunology,
Camille Pelat, and Alessandra Falchi, and Fabrice Carrat, and Anne Mosnier, and Isabelle Bonmarin, and Clément Turbelin, and Sophie Vaux, and Sylvie van der Werf, and Jean Marie Cohen, and Bruno Lina, and Thierry Blanchon, and Thomas Hanslik
May 2011, Vaccine,
Camille Pelat, and Alessandra Falchi, and Fabrice Carrat, and Anne Mosnier, and Isabelle Bonmarin, and Clément Turbelin, and Sophie Vaux, and Sylvie van der Werf, and Jean Marie Cohen, and Bruno Lina, and Thierry Blanchon, and Thomas Hanslik
November 2011, BMC public health,
Copied contents to your clipboard!